变功率加工对激光熔覆成形零件宏观形貌的影响

Effects of Variable Power Processing on Macroscopic Morphology of Laser Cladding Forming Parts

通过创新使用模拟加工过程中实时调控激光功率的方法,对该模拟进行实验验证。获得激光功率的实时改变对于成形温度场和热应力场分布的影响规律;同时也得到了改变加工方法后成形试件的温度云图与宏观形貌特征。结果表明:通过改变激光加工方法,可有效降低成形试样的温度叠加效应与试样成形后的热应力,但达到一定临界点后会降低薄壁件成形效果与粉末利用率。此外改变加工方式还可有效提升试样的高度与可塑性。在实际激光零件加工与修复中,应合理运用加工过中实时改变激光功率的加工方法,既可有效降低成形试样出现加工缺陷的概率,又可提高能源利用率。

The method of real-time controlling laser power in the process of simulating machining was innovatively used.The simulation was verified by experiment.Thereby,the influence law of the real-time change of laser power on the forming temperature field and the thermal stress field distribution was obtained.The temperature cloud image and macroscopic topography of the formed test piece after changing the processing method were also obtained.The results show that that the temperature superposition and thermal stress of the formed sample can be effectively reduced by changing the laser processing method.However,when it comes to a critical point,the forming effect and powder utilization rate of thin-walled parts greatly reduce.In addition,the height and plasticity of the sample can effectively improve by changing the processing method.In the actual processing and repair of laser parts,the processing method of changing the laser power in real time during the processing should be reasonably used,which can not only effectively reduce the probability of machining defects of the formed samples,but also improve the energy efficiency.